Related Experiment Video
Updated: Mar 27, 2026
13:58
Probing C84-embedded Si Substrate Using Scanning Probe Microscopy and Molecular Dynamics
Published on: September 28, 2016
12.3K
Valence band offset at the Si/SiSn interface by applying deep level transient spectroscopy
Victor-Tapio Rangel-Kuoppa1, Alexander Tonkikh, Nikolay Zakharov
1Institute of Semiconductor- and Solid State Physics, Johannes Kepler Universität, A-4040 Linz, Austria.
Nanotechnology
|January 19, 2016
Summary
Hole activation energies in silicon-tin quantum wells increase with tin fraction. Valence band offsets were determined for pseudomorphic and unstrained Si1-x Sn x /Si heterojunctions.
Area of Science:
- Materials Science
- Semiconductor Physics
- Quantum Engineering
Background:
- Silicon-tin (Si1-x Sn x) alloys are promising for optoelectronic applications.
- Quantum wells (QWs) enable precise control of electronic properties.
Purpose of the Study:
- To investigate the activation energies of holes in Si1-x Sn x /Si(001) quantum wells.
- To determine the valence band offsets in these heterostructures.
Main Methods:
- Molecular beam epitaxy (MBE) for growing Si1-x Sn x /Si(001) quantum wells.
- Deep-level transient spectroscopy (DLTS) for measuring hole activation energies.
Main Results:
- Hole activation energies increase monotonically with increasing tin (Sn) fraction (x).
- Valence band offset for pseudomorphic Si1-x Sn x /Si follows ΔE(v) = 1.69x eV.
- Valence band offset for unstrained Si1-x Sn x /Si follows ΔE(v(av)) = 1.27x eV.
Conclusions:
- The Sn fraction is a critical parameter influencing hole behavior in Si1-x Sn x /Si QWs.
- Quantified valence band offsets provide essential data for designing Si1-x Sn x based devices.
Related Concept Videos
01:01Energy Bands in Solids
2.3K
Isolated atoms have discrete energy levels that are well described by the Bohr model. And, it quantifies the energy of an electron in a hydrogen atom as En. Higher quantum numbers 'n' yield less negative, closer electron energy levels.
Band Formation:
When atoms are brought close together, as in a solid, these discrete energy levels begin to split due to the overlap of electron orbitals from adjacent atoms. This split occurs because of the Pauli exclusion principle, which states...
Band Formation:
When atoms are brought close together, as in a solid, these discrete energy levels begin to split due to the overlap of electron orbitals from adjacent atoms. This split occurs because of the Pauli exclusion principle, which states...
2.3K
01:12Fermi Level Dynamics
966
The vacuum level denotes the energy threshold required for an electron to escape from a material surface. It is usually positioned above the conduction band of a semiconductor and acts as a benchmark for comparing electron energies within various materials.
Electron affinity in semiconductors refers to the energy gap between the minimum of its conduction band and the vacuum level and it is a critical parameter in determining how easily a semiconductor can accept additional electrons.
The work...
Electron affinity in semiconductors refers to the energy gap between the minimum of its conduction band and the vacuum level and it is a critical parameter in determining how easily a semiconductor can accept additional electrons.
The work...
966
01:15NMR Spectroscopy: Chemical Shift Overview
3.9K
The position of the absorption signal of a sample is reported relative to the position of the signal of tetramethylsilane (TMS), which is added as an internal reference while recording spectra. The difference between the absorption frequencies of the sample and TMS (in Hz) is divided by the spectrometer operating frequency (in MHz) to obtain a dimensionless quantity called the chemical shift. It is reported on the δ (delta) scale and expressed in parts per million.
For instance, the proton...
For instance, the proton...
3.9K
01:16UV–Vis Spectroscopy: Molecular Electronic Transitions
3.5K
In Ultraviolet–Visible (UV–Vis) spectroscopy, the absorption of electromagnetic radiation is used to probe the electronic structure of molecules. This technique provides insights into molecular electronic transitions, particularly the movement of electrons between different molecular orbitals. Radiation is absorbed if the energy of the electromagnetic radiation passing through the molecule is precisely equal to the energy difference between the excited and ground states. During this...
3.5K
01:25Atomic Absorption Spectroscopy: Interference
2.3K
Interference leads to systematic error in atomic absorption (AA) measurements by enhancing or diminishing the analytical signal or the background. These interferences can be grouped into three main categories: spectral interference, chemical interference, and physical interference.
Spectral interference occurs when signals from other elements or molecules overlap with the analyte signal, falsely elevating or masking the analyte's absorbance. This interference can be corrected using Zeeman,...
Spectral interference occurs when signals from other elements or molecules overlap with the analyte signal, falsely elevating or masking the analyte's absorbance. This interference can be corrected using Zeeman,...
2.3K
01:18Fermi Level
2.3K
The Fermi-Dirac function is represented by an S-shaped curve indicating the probability of an energy state being occupied by an electron at a given temperature. The Fermi level is the energy level at which there is a fifty percent chance of finding an electron, and it is positioned between the lower-energy valence band and the higher-energy conduction band.
At absolute zero temperature, electrons fill all energy states up to the Fermi level, leaving upper states empty. As the temperature rises,...
At absolute zero temperature, electrons fill all energy states up to the Fermi level, leaving upper states empty. As the temperature rises,...
2.3K